"Think about airplanes," Yoshida said during an interview on the sidelines of the Tokyo auto show last month. "They have an autopilot, but when it comes to important operations, the pilot will always take over and the system will support the pilot's maneuvers. So the same with the cars, the driver should be at the center."
Yoshida said Toyota's research in the field will continue at a "very high level," adding that the world's largest automaker would offer automated driving systems but not autonomous driving systems.
In contrast, tech giant Google promises to commercialize the autonomous driving technology within five years, pushing automakers to speed up their r&d.
Daimler and Nissan say that by 2020 they will be ready to offer an autonomous car, and General Motors says it will offer a self-driving feature that can be toggled on and off, like cruise control.
But fully driverless cars will not be a reality "for many years to come," Michael Robinson, a GM vice president who oversees global regulatory issues, said.
Open questions remain regarding liability if a self-driven car causes an accident that injures or kills the car's occupants or others.
Toyota has reason to be concern about taking responsibility away from the driver. Last month a jury in the U.S. state of Oklahoma awarded two plaintiffs $3 million in damages in their case against Toyota.
Lawyers successfully cast doubt on the safety of the electronic throttle system of a 2005 Camry without specifically proving that it caused the car to accelerate out of control in 2007, killing the driver and injuring a passenger.
Last year Toyota moved to settle hundreds of other lawsuits about allegedly out-of-control throttles, agreeing to pay $1 billion.